Initial commit

1 files changed, 70 insertions, 0 deletions

diff --git a/sys/osb/bitfields.c b/sys/osb/bitfields.c
new file mode 100644
index 00000000..3275c542
--- /dev/null
+++ b/sys/osb/bitfields.c
@@ -0,0 +1,70 @@
+/* Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+ */
+
+#define	import_spp
+#define import_knames
+#include <iraf.h>
+
+/*
+ * BITFIELDS.C -- Portable C routines for extracting and inserting small
+ * integers into an integer value.
+ */
+
+unsigned XINT bitmask[] = {	0,		/* MACHDEP		*/
+  01,			    03,			     07,
+  017,			    037,		     077,
+  0177,			    0377,		     0777,
+  01777,		    03777,		     07777,
+  017777,		    037777,		     077777,
+  0177777,		    0377777,		     0777777,
+  01777777,		    03777777,		     07777777,
+  017777777,		    037777777,		     077777777,
+  0177777777,		    0377777777,		     0777777777,
+  01777777777,		    03777777777,	     07777777777,
+  017777777777,		    037777777777,   	     077777777777,
+  0177777777777,	    0377777777777,   	     0777777777777,
+  01777777777777,	    03777777777777,   	     07777777777777,
+  017777777777777,	    037777777777777,   	     077777777777777,
+  0177777777777777,	    0377777777777777,        0777777777777777,
+  01777777777777777,	    03777777777777777,       07777777777777777,
+  017777777777777777,	    037777777777777777,      077777777777777777,
+  0177777777777777777,	    0377777777777777777,     0777777777777777777,
+  01777777777777777777,	    03777777777777777777,    07777777777777777777,
+  017777777777777777777,    037777777777777777777,   077777777777777777777,
+  0177777777777777777777,   0377777777777777777777,  0777777777777777777777,
+  01777777777777777777777,  03777777777777777777777, 07777777777777777777777
+};
+
+
+
+/* BITPAK -- Pack an unsigned integer value into a bitfield in a longword.
+ * The size of the bitfield may not exceed the number of bits in an integer.
+ */
+void
+BITPAK (
+  unsigned XINT	*ival,		/* value to be placed in bitfield	*/
+  unsigned XINT	*wordp,		/* longword to be written into		*/
+  XINT	*offset,		/* one-indexed offset of first bit	*/
+  XINT	*nbits 			/* number of bits to be set		*/
+)
+{
+	register unsigned XINT	shift;
+	register unsigned XINT	mask;
+
+	shift = *offset - 1;
+	mask = bitmask[*nbits] << shift;
+	*wordp = (*wordp & ~mask) | ((*ival << shift) & mask);
+}
+
+
+/* BITUPK -- Unpack an unsigned integer bit field from a longword.
+ */
+XINT
+BITUPK (
+  unsigned XINT	*wordp,		/* longword to be examined		*/
+  XINT	*offset,		/* one-indexed offset of first bit	*/
+  XINT	*nbits 			/* number of bits to be set		*/
+)
+{
+	return ((*wordp >> (*offset-1)) & bitmask[*nbits]);
+}